Pyridotriazole brighteners



United States Patent Office 3,272,830 PYRIDOTRIAZQLE BRIGHTENERS BennettGeorge Buell, Somerville, and Robert Sidney Long, Bound Brook, N.J.,assignors to American 3,272,830 Patented Sept. 13, 1966 in which M is anaphthalene ring which may carry halogen, alkyl, alkoxy and sulfogroups, and quaternary salts thereof.

Cyanarnid Company, New York, N.Y., a corporation 5 of Maine No Drawing.Application Apr. 19, 1962, Ser. No.

188,897, now Patent No. 3,222,371, dated Dec. 7, 1965, which is adivision of application Ser. No. 87,754, Feb. N X W 8, 1961, which inturn is a division of application Ser. in which X may be hydrogen, sulfoor cyano; W may be 693,930 110W Patfmt Q- ,9 hydrogen or sulfo and Z maybe hydrogen, sulfo, amino dated Oct. 16, 1962. Divided and thisapplication Aug. or b i d amino, and quaternary salts thereof. 25, 1964,Ser. No. 392,047 (4) U 1 Claim. (Cl. 260-295) N\ /N This application isa division of application SN. -0 188,897, filed April 19, 1962, nowPatent No. 3,222,371 I'IQN which application is in turn a division ofSN. 87,754, N N Q T irrita in ;margarita Q be 0, NH or U he or .g, f t930, filed November 26, 1957, now Patent No. 3,058,989. may be hydmgeSul and qua 6mm This invention relates to organic fibers dyed with com-(5) pounds of the structure: Y /N N Y /N 1 m N ov HZN in which Q may be0, NH or S; and V may be hydrogen,

N H alkyl, or aryl, and quaternary salts thereof.

6 in which Y may be hydrogen, alkyl, halogen, carboxy, 0 Y N N Ycarbalkoxy or carboxamido, n may be one or two and R is an organicradical having a o-membered aromatic N-OO-N ring directly bonded to thetriazole rings, the said group HzN- NH R being the residue ofadiazotizable amine. This inven- N N N N tion further relates to variousnew compounds of difi'erin which the biphenyl moiety may carry onesulfonic acid ent structures which may be used to dye and to brightengroup ortho to the biphenyl bond, and quaternary salts organic fibers.More specifically, it relates to each of thereof.

7) Y N N Y N- -OH=CH N HEN NHQ N 5 the separate and distinct groups ofcompounds listed in which D and B may be hydrogen or sulfo, andquaterbelow: nary salts thereof.

a Y N N Y a N H1 HQN I N R2 HQN N/ F \N/ NH? in which R; may behydrogen, halogen, alkyl, alkoxy, amino, acylamino, carboxy or phenyl, Rmay be hydroin which F may be hydrogen or lower alkyl, and quatergen,alkyl or halogen, one of R and R not being hynary salts thereof. drogen,and Y being defined as above in this and each succeeding formula andquaternary salts thereof. (9 Y N Y 2 Y N i I N-M HZN zN N \S02 N andquaternary salts thereof.

(10) Y N Y and quaternary salts thereof.

in which L may be hydrogen, methyl, methoxyl, or chloro, and quaternarysalts thereof.

in which B is a S-pyrimidyl radical, and quaternary salts thereof.

in which G and G can be the residue of an aliphatic amine such asethanolamine or diethanolamine or of an aromatic amine or aminosulfonicacid, and quaternary salts thereof.

Optical bleaching agents or brighteners are widely used in whitening andbrightening textile fibers of various types and are used both during themanufacture of textiles and during the operation of laundering fabrics.When optical bleaching agents or brighteners are applied to cloth, theblue fluorescence of the brightener, excited by ultraviolet irradiation,acts to neutralize the yellowish color of the cloth, producing awhitening and brightening effect. Like any dye-stuff, a necessaryproperty is substantivity on the cloth. Brighteners are applied fromvery dilute solution, and unless they are substantive on the cloth, andthus are not readily washed off, the effect will not be achieved.Various types of compounds are used as brighteners and no brightener isequally substantive on all fibers. Most brighteners are relativelynon-substantive to one or another fiber, and consequently, differenttypes of brighteners must be used for different types of fabrics.Compounds which are suitable for cellulose fibers such as cotton, areoften not usable for synthetic fibers such as polyacrylonitriles orsuperpolyamides. Brighteners which show substantivity on most commontextiles-are a great need in the industry. While it is possible that nosingle brightener will ever be completely universal in its application,extensive research has been done in the search for at least a class ofcompounds which will be readily usable on any fiber or which willinclude members approaching universality of application.

The fluorescence of brighteners usually ceases immediately upon theremoval of the source of ultraviolet light. Phosphorescence, or thecontinuation of emission of visible light for an appreciable time afterremoval of the ultraviolet source, is not a necessary characteristic fora brightener. However, phosphorescence is a property which is usable inother ways and whose importance is rapidly increasing. A particularlyimportant application for phosphorescent compounds is in a machine inwhich the phosphorescent property is used for the purpose of weftstraightening. This is a process in the textile field for maintainingfill threads perpendicular to warped threads and selvages. Thephosphorescent effect allows control through the use of photocells whichare activated by the difference in the period of light emission byfluorescent compounds which phosphoresce, and those which do not. It isnecessary to use phosphorescent compounds in such weft straighteningbecause of the almost universal use of brighteners in the finishing ofcloth. Heretofore the control Was through the fluorescence of a threaddyed specially with a brightener, but now, with all threads being dyedwith brighteners, the machine will not operate satisfactorily.Consequently, as described by Allen in his specification, Ser. No.644,886 filed March 8, 1957, the control is now carried out by dyeingthe control threads with a phosphorescent 'brightener, which thuscontinues emitting light after the source of ultraviolet is removed.

For use in such an application, a compound must possess other propertiesbesides fluorescence and phosphorescence. It is necessary that thecompound be stable to various chemical and physical treatments whenapplied to the fiber or a fabric without losing the phosphorescentproperty and without being removed from the fiber or the fabric. Mostcompounds, even when they show some phosphorescence, do not withstandthe harsh treatment necessary in the finishing of fabrics. Suchtreatment includes caustic solution at elevated temperatures, bleachingwith hydrogen peroxide, steaming, and the like. There is thus a furtherneed in the dyestuif field for a class of compounds which willphosphoresce and also which will be stable under the harsh treatments oftextile manufacture.

We have found that organic fibers can be dyed readily with compounds ofthe formula:

r Y N R e v l in which Y may be hydrogen, alkyl, halogen, carboxy,carbalkoxy or carboxamido; n may be 1 or 2, and R is an organic radicalhaving a 6-membered aromatic ring directly bonded to the triazole rings,to the said group R being the residue of a diazotizable amine, and thatsuch organic fibers exhibit phosphorescence and fluorescence and arestable to the various conditions of textile manufacture. We have furtherfound that these dyestuffs can be applied to a great variety of fibers,many of them being applicable to a greater or lesser extent to nearlyall organic fibers and that, with variations in the structure, it ispossible to increase the substantivity of such compounds on specificclasses of organic fibers. We have further found several distinctclasses of new compounds as listed above, which form a separate aspectof our invention. These classes of compounds are not equivalent, theirsubstantivity on various fibers, their color (i.e., either fluorescenceor self-color as dyes), their phosphorescence and their stability tovarious treaments varying from group to group.

It is an advantage of our invention that by proper selection ofsubstituents, it is possible to obtain dyeings on a wide range oforganic fibers. It is known that brighteners tend to be substantive oncellulosic fibers when they are linear coplanar molecules havingextended conjugation. It is surprising however, that the compounds usedin our invention go on cellulosic fibers even when these structuralcharacteristics are not prominent. Thus,2-phenyl-6-amino-2,3-pyridotriazole is substantive on cotton, althoughit is not an extended liner coplanar molecule, nor is it sulfonated.However, when the substituent on the triazole ring is a simple arylgroup, one obtains optimum brightening only on polyacrylonitrile fibers.Cotton brightening is obtained more readily with the use of morecomplicated substituents on the triazole ring or, better yet, evenbis-ltriazoles. It is a further advantage of our invention that onereadily obtains good acid solubility with pyridotriazoles, as contrastedto benzoor naphthotriazoles. It is a further advantage of our inventionthat the pyni dotriazoles have good aflinity to many kinds of syntheticfibers, especially polyamides and polyacrylonitriles. It is a stillfurther advantage of our invention that the pyridine ring in thepyridotriazole nucleus can be quaternized with the result that increasedsolubility is obtained and afiinity is obtained on polyacrylonitrilefibers at a wide range of pHs.

In the preparation of compounds substantive to particular fibers,attention must be given to such factors as the type of fiber to betreated, the method of application Gand the solubility properties),whether the desired effect is phosphorescence or fluorescence (and iffluorescence, whether reddish-blue or greenish-blue) and similarfactors. When solubility in Water is important, sulfonated aryl residuescan be used. However, sulfonation has the effect of decreasing affinityon polyacrylonitrile fibers and similar non-cellulosic fibers. Greenershades of fluorescence can be attained by using suitable auxochromicsubstituents such as alkoxyl, dialkylam-ino or acylamino. One of themost useful and at the same time most unexpected advantages of thepresent invention is the wide variety of effects which can thus be builtinto the products by proper selection of the starting materials.

The dyestuffs used in the present invention are conveniently prepared bycoupling an aromatic diazonium compound with a 2,6-diaminopyridine toform a 3-arylazo-2,6-diaminopyridine, which is then triazolized by anoxidative ring closure method using a mild oxidizing agent. If it isdesired to quaternize, this is achieved by reaction of the triazoleproduct with an alkylating agent such as an alkyl halide. Variousaromatic amines may be used to form the diazo component in the firststep of this preparation and proper selection of the amine makes itpossible to produce an optical bleaching agent with properties making itsuitable for use on various textile fibers. Examples of diazotizableamines which may be used in the reaction to produce compounds of theinvention are:

aniline pand m-aminobenzoic acid alkyl and aryl pand m-aminobenzoatespand m-aminobenzenesulfonic acid and their alkyl and aryl esters pandm-aminobenzenealkyl sulfones pand m-aminoacetanilide andm-aminobenzanilide and m-aminoanisanilide and m-aminobutyranilide andm-toluidine and m-chloroianiline and m-bromoaniline and m-fluoroanilineo-xylidine 3,4-dimethylaniline) pand m-anisidine pand m-nitroaniline4-aminobipheny1 benzidine 4-aminostilbene4,4-diaminostilbene-2,2'-disulfonic acid 2-naphthylamineZ-aminonaphthalene-6-sulfonic acid 2-aminonaphthalene-5-sulfonic acid2-aminonaphthalene-S,7-disulfonic acid 2-aminonaphthalene-6,8-disulfonicacid 2-(p-aminophenyl)-benzimidazole, benzoxazole and benzothiazole 5-and 6aminobenzoxazole, -benzothiazole, -benzimidazole, -benzotriazole4-aminopyridine 3-aminopyridine 6-methOXy-Z-naphthylamine6-chloro-2-naphthylamine These diazos are coupled with various2,6-diaminopyridines such as the following:

2,6-diaminopyridine 2,6-diarnino-3-methylpyridine2,6-diamino-4-methylpyridine 2,6-diaminopyridine-4-carboxylic acid andits esters 2,6-diamino-3-bromopyridine 2,6-diamino-4-bromopyridine2,6-diaminopyridine-4-carboxamide The 3-arylazo-2,6-diaminopyridineintermediate is then oxidized with a mild oxidizing agent such as air inthe presence of copper sulfate, which results in ring closure to thetriazole derivative.

Pyridotriazoles in which the substituent on the triazole ring is apara-ami-nophenyl radical form an especially useful class of compoundsfor use in our invention, since they can be intermediates for thefurther preparation of more complicated brighteners and phosphorescentagents which can also be used in our invention. For example, the aminogroup on this phenyl ring can be diazotized and coupled into othercoupling components and, when the coupling component is so constitutedthat an o-aminoazo compound is formed, this too can be triazolized togive a bisor poly-triazole derivative. Thus, a bis-triazolo compound,either symmetrical or unsymmetrical is readily produced. The symmetricalbis-triazole compounds are also readily produced from tetrazotization ofan aromatic diamine.

The fibers which may be used in preparing the dyed fibers of ourinvention include the various organic fibers used in the textileindustry, bot-h synthetic and natural, since substantivity and otherproperties can be varied by the choice of the proper substituents andthe proper ring groupings in the brightener molecule to favorsubstantivity on any particular type of fiber. Among the fibers whichmay be used are the natural fibers, both cellulosic and non-cellulosic,such as cotton, wool, silk, and the like, and the synthetic fibers ofboth the cellulosic and non-cellulosic types such as viscose rayon(i.e., regenerated cellulose) cellulose esters such as celluloseacetate, polyacrylonitrile (either the homopolymer or copolymers withvarious comonomers such as vinyl pyridine, methyl acrylate, vinylchloride, and the like), superpolyamides such as hexamethylenepolyadipamide and poly-omegaaminocaproamide, and superpolyesters such aspolymeric glycolterephthalate.

The brighteners to be used in our invention are especially useful onthose fibers for which most known brighteners have been notsatisfactory, such as the polyacrylics and the superpolyesters.

The brighteners may be applied as optical bleaching agents or asphosphorescent agents from detergent compositions as ordinarilyformulated in the art, or from rinsing liquors for treatment duringtextile manufacture or after laundering operations.

In addition to being useful as brightening agents, the products used inthe preparation of our invention are also phosphorescent and thus thedyed fibers of our invention can be used where phosphorescence isimportant for special effects. 2-phenyl-6-amino-pyridotriaz-ole isespecially useful for this purpose because of its phosphorescence andits substantivity to a wide variety of fibers. A particularly importantapplication for such phosphorescent dyed fibers is in a machine in whichthe phosphorescent property is utilized for the purpose of WeftStraightening, a process in the textile field for maintaining fillthreads perpendicular to warp threads and selvages. As described above,it is necessary for such application to have compounds which will standrather drastic treatment. It is an advantage of the dyed fibers of ourinvention that they are able to withstand the treatment with causticsolution at elevated temperatures and similar drastic treatments, andthat they show sufiicient phosphorescence.

Our invention includes not only organic fibers dyed with a broad classof pyridotriazole compounds, but also specific groups falling withinthis broad class of compounds which have distinct and separateproperties. These are all prepared in the same manner as described ingeneral for the class, i.e., by the coupling of an aromatic diazocompound into a 2,6-diaminopyridine. Thus, in each class the pyridineswhich may be used as the starting material are the same, but thediazotizable amine which is used varies with the class of compoundsbeing considered.

In the class of compounds of the structure:

the amino compounds which may be used as starting materials include.

p-chloraniline p-toluidine p-anisidine p-phenetidine p-nitroanilinep-phenylenediamine monoacylated p-phenylenediamines; such asp-acetamidoaniline p-benzamidoaniline p-propionylamino-aniline, and thelike p-aminobenzoic acid 4-aminodiphenyl 4-chlor-3-methylaniline4-bromo-3-ethylaniline 4-chlor-3-butylaniline 3,4-dichloroaniline3chlor-p-anisidine m-bromaniline, and the like.

The amines which may be used to prepare compounds of the class of thestructure:

include beta-naphthylamine, 2-aminonaphthalene-6-sulfonic acid,2-aminonaphthalene-S-sulfonic acid, Z-aminonaphthalene-4,6-disulfonicacid, 2-aminonaphthalene-S,7- disulfonic acid,Z-aminonaphthalene-6,8-disulfonic acid, Z-aminonaphthalene 4,8disulfonic acid, 6-methoxy-2- naphthylamine, 6-chloro-2-naphthylamiue,and the like.

The amines which can be used to prepare the compounds of the structure:

include 4-aminostilbene, 4-aminostilbene-2,2'-disulfonic acid,4-aminostilbene-Z-sulfonic acid, 2-cyano-4-aminostilbene, 4-amino-4nitrostilbene-2,2'-disulfonic acid, 2- (4-aminostilbyl)-methyl sulfone,and the like.

The amines which may be used to prepare the class of compounds of theformula:

Br m Q I T include dehydrothiotoluidine, dehydrothiotoluidine sulfonictacid, 4-amino-2-phenyl benzox azole, 4'-amino-2- phenyl-benzimidazole,and the like.

In the preparation of compounds of the class:

the following amines may be used; 5- or 6-aminobenzothiazole,Z-methyl-S- or 6-aminobenzothiazole, 2-phenyl- 5- or6-aminobcnzothiazole, 5- or 6-aminobenzoxazole, 2-phenyl-5- or6-aminobenzoxazole, 2-methyl'5- or 6- aminobenzoxazoles,S-aminobenzimidazole, Z-methyl-S (6)-aminobenzimidazole,2-pheny1-5(6)-aminobenzimidazole, and the like.

In the preparation of compounds of the structure:

the starting material which is used as the diazotizable amine may bebenzidine or a benzidine monosulfonic acid in which the sulfonic acidgroup is ortho to the biphenyl bond.

Compounds of the type:

can be prepared starting with such compounds as4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl methyl amine, 4,4diaminodiphenyl ethyl amine, 4,4 diaminodiphenyl butyl amine, and thelike.

The starting material for compounds of the structure:

is 3,7-diamino-dibenzothiophene-5,5-dioxide.

Compounds of the formula:

are prepared from 4,4'-diamino-N,N-diphenylurea.

Compounds of the structure:

are prepared by starting with either para-nitroaniline for the firstcoupling into the 2,6-diaminopyridine derivative or similarly from anacylaminoaniline. After this first coupling, either the nitro group isreduced or the acyl group is hydrolyzed and the freed amino group isthen diazotized and coupled into a naphthylamine, followed bytriazolization. The n-aphthy-lam'ine can be 2 niapht'hylamine, 2na-phthylamine 4 sulf onic acid, 2 naphthylamine-S-sul-fionic acid,naphthionic acid, Laurents acid, 2-naphthyIamine-G-sulfonic acid,Z-naphthylamine-S- sulfonic acid, 2-naphthylamine-4,6-, 5,7- or6,8-disulfonic acid, 6-methoxy-2-naphthylamine, 6-chloro 2naphthylamine, and the like.

The compounds of the structure:

in which B is a SQ-pytrimidyl nucleus are obtained by coupling adiiazotized amino pyrimidine into a 2,6d-iamino pyridine andtriazolizing. For this purpose one can use S-amino pyrimidine,substituted 5-amino pyrimidines, and the like.

Compounds of the type:

are prepared by reacting the intermediate 2p-aminophenyl-6-amino-pyridotriazole with cyanuric chloride, fol- 7 5lowed by further reaction of the product with aliphatic amines such asalkyl amines or preferably substituted alkylamines (ethanolamine,diethanolamine, morpholine, etc.) or with aromatic amines oraminosulfonic acids such as aniline, sulfanilic acid, and the like.

In all these various classes of dyestuffs, as well as in the principalinvention of the dyed fibers, the pyridine ring in the pyridotriazolemoiety can be quaternized by treatment with an alkylating agent to forma quaternary compound on the pyridine ring nitrogen. Examples ofalkylating agents which may be used are methyl iodide, ethyl bromide,butyl bromide, benzyl bromide, dimethyl sulfate, diethyl sulfate,ethylene chlorohydrin, beta-diethylamino ethyl chloride, alkyl tosylatessuch as methyl tosylate, and the like.

Among the purposes of such quaternization are to get increased watersolubility of the brightener molecule and to permit the application ofthe dyestutf over a broader range of pH. The quaternized brighteners arein general equivalent to the unq uaternized brighteners, and in somecases superior, in substanttivity to various fibers. Consequently, thequaternized compounds and the fibers dyed with them form a part of ourinvention.

()ur invention can be illustrated by the following examples in whichparts are by weight unless otherwise indicated.

Example 1 A mixture of 27.9 parts of 2,6-diarnin'o-3-phenyl-azopyridine(commercially available as Pyiridium or Azoimide), 450 parts of ethanol,parts of water and 180 parts of concentrated ammonium hydroxide isheated under reflux with stirring. A hot solution of 170 parts of coppersulfate in 500 parts of water and 300 parts of concentrated ammoniumhydroxide is added. After heating for several hours, an additionalportion of 25 parts of copper sulfate in parts of water and 45 parts ofconcentrated ammonium hydroxide is added and heating is continued untilthe reaction is substantially complete, as shown by disappearance of thestarting material. After cooling the mixture, the product is removed byfiltration and washed thoroughly with dilute ammonium hydroxide andwater to remove the copper. The product is purified by dissolving in 400parts of water, 450 parts of ethyl alcohol, and parts of concentratedhydrochloric acid. After treatment with a decolorizing agent andfiltering, the filtrate is treated with 55 parts of concentratedhydrochloric acid. On cooling, the hydrochloride of the productseparates as cream-colored rods, is removed by filtration and thenwashed with alcohol.

ExampleZ /N O IIQN \N N s o Na A idiazoniulm solution is prepared from2.75 parts of 4-amin0-stilbene2-sulfonic acid by diazotization withsodium nitrite. The diazonium solution is combined with a solution of1.09 parts of 2,6-diaminotpyridine in 75 parts of acetic acid, 50 partsof water and 2.2 parts of concentrated hydrochloric acid. With stirring,50 parts of a saturated solution of sodium acetate is added slowly andstirring is continued until coupling is complete. The solid aminoazocompound is removed by filtration and washed with water and is thentaken up in 90 parts of 95% ethanol, 22 parts of concentrated ammoniumhydroxide and 20 parts of water. The mixture is heated to the boilingpoint and a hot solution of 17 parts of copper sulfate, 75 parts ofwater, and 36 parts of concentrated ammonium hydroxide is added and themitxure is heated at the reflux temperature with stirring until thereaction is complete. After the mixture is cooled, the solid is removedby filtration, slurried in dilute hydrochloric acid and then againisolated by filtration. For purification, it is dissolved in methylCellosolve containing a small amount of sodium hydroxide and afterclarification with a decolorizing agent, the product is isolated fromthe filtrate by adding additional sodium hydroxide solution andsaturated sodium acetate. After stirring, th product is isolated as 'alight tan sodium salt.

Example 3 Example 4 \NAN/ @Q A diazonium solution is prepared bydiazotizing 3.38 parts of 4-arninobiphenyl with sodium nitrite in aceticacid at 30 C. The diazonium solution is combined with a solution of 2.18parts of 2,6-diaminopyridine in 100 parts of acetic acid, 100 parts ofwater, and 4 parts of concentrated hydrochloric acid. With stirring, 75parts of saturated sodium acetate solution is added. The mixture isstirred until the coupling is complete and the light orange couplingproduct is removed by filtration and triazolized by oxidation withcopper sulfate and ammonium hydroxide as described in Example 2. Theproduct is purified by dissolving in about 600 parts of hot methylCellosolve and excess concentrated hydrochloric acid, clarifying with adecolorizing agent and isolating by the addition of 300 parts of waterand excess ammonium hydroxide to the filtrate.

Example 5 The procedure of Example 4 is followed except that anequivalent quantity of 2,6-diamino-3-bromo-pyridine is used in place ofthe 2,6-diaminopyridine and an equivalent quantity of aniline is used inplace of the 4-aminobiphenyl. The corresponding methyl compound isprepared by starting with 2,6-diamino-3-methyl-pyridine.

Example 6 The procedure of Example 4 is followed except that anequivalent quantity of 2,6-diamino-4-picoline is used in place of the2,6-diaminopyridine.

Example 7 A diazonium solution is prepared by diazotizing 13.8 parts of4-nitr0-aniline with sodium nitrite. The solution is combined with asolution of 10.9 parts of 2,6-diaminopyridine in 500 parts of aceticacid, 500 parts of water and 18 parts of concetrated hydrochloric acid.With stirring, the mixture is neutralized with saturated sodium acetatesolution and the bright red o-aminoazo product which forms is removed byfiltration and washed with water. This o-aminoazo product is taken up in540 parts of ethanol, 150 parts of water, and 135 parts of concentratedammonium hydroxide. The mixture is heated and a hot solution of 125parts of copper sulfate, 500 parts of water, and 225 parts of ammoniumhydroxide is added. The mixture is heated at the reflux temperatureuntil the triazolization is complete, cooled, and the product is removedby filtration. This nitro compound is then reduced to the correspondingamino compound by the following procedure:

The nitro compound is added to 150 parts of water, parts of ethanol and120 parts of 5 N sodium hydroxide. To the mixture at -85 C. is added 70parts of sodium hydrosulfite. After stirring and cooling, the product isisolated by filtration and washed alkali-free with water. The aminocompound is purified by clarification with a decolorizing agent fromsolution in 250 parts of hot 4 N hydrochloric acid, and isolated bymaking the filtrate alkaline by the addition of ammonium hydroxide.

Example 8 To 0.75 part of 6-amino-2-(p-aminophenyl)-2-pyrido[2,3-d]-v-triazole (prepared as in Example 7) is added 25 parts ofpyridine and 0.7 part of p-anisoyl chloride. The mixutre is heated atthe reflux temperature for a short time and is then drowned in ice. Thesolid product which forms is removed by filtration and washed with waterand is purified by recrystallization from methyl Cellosolve, giving theproduct in the form of prisms with a melting point of 293296 C.

By the use of equivalent amounts of other acyl halides in place of thep-anisoyl chloride such as acetyl chloride, butyryl chloride, stearylchloride, benzoyl chloride, 2,4- dichlorobenzoyl chloride, and similarcompounds, the corresponding acylamide compounds are obtained.

Example 9 S O;Na

// \N N/ \N/ Q until the coupling is complete (4 hours). The o-aminoazoproduct is removed by filtration and triaz-olized by oxidation using theprocedure described in Example 7. Purification of this bis-triazolylproduct is effected by dissolving the product in 400 parts of hotmonoethanolamine, and 4 parts of 5 N sodium hydroxide solution. Afterclarification with a decolorizing agent, 100 parts of water is added tothe filtrate and the sodium salt of the product is salted out by theaddition of sodium hydroxide, giving a crystalline yellow product.

A tetrazonium solution prepared by tetrazotizing 1.86 parts of benzidinein 100 parts of water, 9 parts of hydrochloric acid and 8 parts of 1 Nsodium nitrite solution is combined with a solution of 2.4 parts of2,6-dia-minopyridine in 100 parts of water and 5 parts of concentratedhydrochloric acid. The mixture is neutralized to Congo Red Indicator byaddition of saturated sodium acetate solution (about 60 parts). Thecolor changes from blueblack to dull-orange. After stirring the mixture,the solid azo product is removed by filtration.

For conversion to the triazole derivative the disazo product from aboveis slurried in a hot mixture of 150 parts of pyridine and 20 parts ofconcentrated ammonia. A half-portion of a solution of 24 parts of coppersulfate,

100 parts of water and parts of ammonia is added and the mixture isheated for several hours. The other half of the copper sulfate solutionis then added and the mixture is heated until the reaction is complete.The solid material is removed by filtration and purified byrecrystallization from about 300 parts of N-methyl-2-pyrrolidone.

Example 11 A tetrazonium solution is prepared by tetrazotizing 37 partsof 4,4-diaminostilbene-2,2'-disulfonie acid. This is done by firstdissolving the stilbene derivative in 150 parts of water and 7 parts of5 N sodium hydroxide solution. Twenty-one parts of l N sodium nit-ritesolution is added and after filtering, the solution is poured into amixture of 200 parts of ice and 16 parts of hydrochloric acid. Afterstirring for a short period, the excess nitrite is destroyed withsulfamic acid.

To the above brown slurry is added a solution of 2.4 parts of2,6-diamino-pyridine in 150 parts of water and 5 parts of concentratedhydrochloric acid. Saturated sodium acetate solution is added until themixture is neutral to Congo Red Indicator. Coupling takes place rapidlyand after stirring, the solid disazo compound is removed by filtrationand triazolized by the procedure described below.

The solid product is dissolved in a hot mixture of 150 parts of pyridineand 20 parts of ammonium hydroxide. To this is added a half portion of asolution of 24 g. copper sulfate, 100 parts of water and 20 parts ofconcentrated ammonia. After heating a short period, the second halfportion of the copper sulfate solution is added and the mixture isheated until the reaction is complete. The solid bis-triazolo compoundis removed by filtration.

The product may be purified by recrystallizing from hot dimethylformamide containing a small amount of caustic and then precipitatingthe product from the cooled dimethyl-formamide filtrate by addition ofwater and hydrochloric acid to the neutral point.

SO Na A diazonium solution prepared by diazotization of 2.26 parts of6-amino-2-(p-aminophenyl)-2-pyrido-[2,3-d]-triazole with sodium nitritein hydrochloric acid solution is combined with a solution of 3.04 partsof 6-amino-2H-5- methyl-Z-(p-sulfophenyl)-benzotriazole in 160 parts ofacetone, parts of water and 4 parts of concentrated hydrochloric acid.With stirring, 50 parts of saturated sodium acetate solution is addedand the mixture is then stirred until the coupling is complete (4hours). The resulting o-aminoazo product is removed by filtration andthen triazolized by oxidation with copper sulfate using the proceduredescribed in Example 6. The product is isolated as the sodium salt andpurified by treatment with decolorizing charcoal in hot dimethylformamide solution, giving the product as the purified sodium salt.

Example 13 COOH The procedure of Example 1 is followed except that anequivalent amount of 2,6-diaminopy-ridine-4-carboxylic acid is used inplace of the 2,6-diaminopyridine.

Example 14 Example 15 %N W -Q 's /s Ha The procedure of Example 4 isfollowed using an equivalent quantity of 3,4-dimethylaniline in place ofthe 4-aminobiphenyl. Similarly, other substituted products are obtainedif one uses 3-chloro-4-methyl-aniline or 4-ch1or0-3-methy-laniline inplace of the dimethylaniline.

Example 16 The procedure of Example 4 is followed using an equivalentquantity of beta-naphthylamine in place of the 4-aminobi-phenyl.Corresponding substituted compounds are obtained by using suchderivatives as Bronners acid, Dahls acid, amino J acid and amino G acidin place of beta-naphthylamine.

Example 17 The procedure of Example 4 is followed using 4- aminostilbenein equivalent quantities in place of the 4-aminobipheny-l. The productis a good brightener for nylon.

Example 18 N/\N/ ON A mixture of 30 parts of 2-cyano-4-nitrotoluene, 22parts of benzaldehyde and 5 parts of piperidine is heated at 125 140 C.until the reaction is substantially complete. The melt is dissolved in160 parts of hot glacial acetic acid and on cooling the crystallinesolid which forms is filtered. To a boiling suspension of 9 parts of theabove product in 250 parts of 95% alcohol is added a solution of 44parts of hydrated stannous chloride and 44 parts of concentratedhydrochloric acid. The mixture is heated at reflux temperature untilreduction is substantial-1y complete. The mixture is then cooled and thesolid is removed by filtration. It is purified by slurrying in dilutesodium hydroxide solution.

A solution of 4.4 parts of the 4-amino-2-cyanostilbene so produced in120 parts of acetic acid is prepared and to it is added 8.4 parts ofconcentrated hydrochloric acid. Twenty-two parts of N/l sodium nitritesolution is then added with cooling, and after stirring for a shortperiod the excess nitrite is discharged by the addition of sulfamicacid. The diazo solution is then used to couple with a solution of 3parts of 2,6-diaminopyridine in 100 parts of acetic acid, 100 parts ofwater and 4 parts of concentrated hydrochloric acid by the procedure ofExample 4.

Example 19 HzN N \N/ (IJN S OaH To a hot well-stirred solution of 22.9parts of the sodium salt of benzaldehyde ortho su-lfonic acid and 16.2parts of S-nitro-orthotoluonitrile in 40 parts of pyridine there isadded 2 parts of piperidine and 9.2 parts of sodium bicarbonate. Themixture is heated on a steam bath until the reaction is substantiallycomplete. During the heating period, an additional 40 parts of pyridineis added. The mixture is then diluted with 200 parts of water and thepyridine is stripped out with steam. The mixture is cooled with ice andthe precipitated product is isolated by filtration and dried.

To a vigorously stirred mixture of 29.5 parts of iron powder, 150 partsof Water and 4 parts of glacial acetic acid heated under reflux there isgradually added 11.8 parts of the product of the preceding paragraph.The mixture is heated under reflux with good stirring until the reactionis substantially complete and then is neutralized with a small excess ofsoda ash. The iron sludge is filtered and washed with hot methanol andthe filtrate and washings are treated hot with charcoal. The mixture isfiltered and the filtrate is acidified with concentrated hydrochloricacid. The precipitated 4-amino-2-cyanostilbene-2-sulfonic acid isisolated by filtration and purified by recrystallization from alcoholicmethanol followed by reprecipitation with hydrochloric acid.

An equivalent quantity of the above product is use-d in the procedure ofExample 2 in place of the 4-aminostilbene-2-sulfonic acid used in thatexample.

Example 20 The procedure of Example 2 is followed using an equivalentquantity of 4-amino-4'-nitrostilbene-2,2'-disulfonic acid. The nitrogroup is then reduced and acylated as in Example 8, using benzoylchloride.

Example 22 The procedure of Example 4 is followed using an equivalentquantity of 4'-amino-2-phenylbenzoxazole in place of the4-aminodiphenyl.

Example 23 The procedure of Example 4 is followed using an equivalentquantity of 4-amino-Z-phenylbenzimidazole in place of the4-amino-biphenyl.

Example 24 The procedure of Example 4 is followed using an equivalentquantity of S-aminobenzothiazole in place of 4- aminodiphenyl.Similarly, equivalent quantities of 5- I 7 amino-Z-methylbenzothiazoleand -amino-2-phenylbenzothiazole can be used to give the correspondingsubstituted products.

Example 25 N Q HzN N o The procedure of Example 10 is followed using anequivalent quantity of 3,8-diaminodibenzothiophene-5,5'- dioxide inplace of the benzidine. The corresponding sulfonated products areprepared by following the procedure of Example 11 using as startingmaterials equivalent amounts of3,8-diaminodibenzothiophene-5,5'-dioxide-2,7-disulfonic acid or thecorresponding monosulfonic acid.

Example 31 HiN \N N/ \N, NH,

The procedure of Example 4 is followed using 6-amino-2-phenylbenzoxazole in equivalent quantities in place of 4-:aminodiphenyl. If 6-aminobenzoxazole or 6-amino-2- methylbenzoxazole isused in equivalent quantities the corresponding brightener compound isobtained.

Example 26 /N N\C-CH; mlfllj x The procedure of Example 4 is followedusing an equivalent quantity of 5(6)-amino-2 methylbenzimidazole inplace of 4-aminodiphenyl.

Example 27 v F H2N \N \N/ 40.11 \N/ N/ NE,

The procedure of Example 11 is followed using an equivalent quantity ofbenzidine-Z-sulfonic acid in place of diaminostilbene disulfonic acid.

Example 28 The procedure of Example 10 is followed using an equivalentquantity of 4,4'-diaminosti1bene in place of the benzidine. Thecorresponding monosulfonic acid is prepared if the procedure of Example11 is followed with 4,4'-diaminostilbene monosulfonic acid.

Example 29 The procedure of Example 10 is followed using an equivalentquantity of 4,4-diaminodiphenylamine in place of the benzidine. Thecorresponding alkyl compounds are prepared if equivalent quantities of4,4-diphenylmethylamine and 4,4'-diphenylbutylamine are used in place ofthe 4,4'-diphenylamine above.

Example 30 The procedure of Example 10 is followed using an equivalentquantity of 4,4'-diaminodiphenylurea in place of the benzidine.

Example 32 SOaH The procedure of Example 9 is used usingZ-naphthylamine-S-sulfonic acid in place of naphthionio acid. Thecorresponding disulfonated product is obtained by using an equivalentquantity of 2-na-phthy1amine-4,6-disulfonic acid in place of thenaphth-ionic acid. If the naphthionic acid is replaced withbeta-naphthylamine the corresponding unsulfonated product is obtained.

Example 33 N NH:

A mixture of 1 part of S-amino-Z-pheny-l-(2)-pyrido- [2,3-d14v-triazole(prepared as in Example 1), 40 parts of methanol and 44 parts of methyliodide is heated at the reflux temperature until the reaction iscompleted, and is then evaporated to dryness. The yellow solid which isobtained is purified by precipitating [from a methanol 19 Example 34 Amixture of 21 parts of -amino-2-phenyl-(2)-pyrido- [2,3-d] -v-triazole,24 parts of diet-hylsulfate and 100 parts of ethanol is heated at thereflux temperature until the reaction is complete.

The crystalline solid which forms is removed by filtration.

By using an equivalent amount of dimethyl sulfate in place of thediethyl sulfate, the corresponding methyl compound is obtained.

Example 35 A mixture of 21 parts of 5-amino-2-phenyl-(2)-pyrido-2,3-d-v-triazole, 32 parts of methyl p-toluene-sulfonate and 100 partsof ethanol is heated at the reflux temperature until the reaction iscomplete. After cooling, the solid is removed by filtration giving awater soluble product.

When the methyl p-toluene sulfonate is replaced by an equivalent amountof methyl p bromobenzene sulfonate the corresponding p bromobenzenesulfonate salt is obtained.

Example 36 The procedure of Example 33 is followed using the product ofExample 6 instead of the product of Example 1. The product of the abovestructure shows more aflinity for some fibers than does the product ofExample 6 and on other fibers is equivalent to the unquaternizedproduct.

Example 37 2 \N \N/ Br The diazonium solution from 0.03 mole ofm-bromoaniline is combined with a chilled solution of 3.27 parts (0.03mole) of 2,6-diaminopyridine in 225 parts of water and 5 parts ofconcentrated hydrochloric acid. Twentyfive parts of a saturated solutionof sodium acetate is added dropvvise with stirring. The mixture isstirred until the coupling is completed. .An orange product is filteredand allowed to drain.

The product is taken up in 92 parts of ethanol, 16 parts of Water, 45.8parts by volume of concentrated ammonia and 10 parts of pyridine and themixture is heated with stirring. A hot solution of 38.9 parts of coppersulfate in 115 parts of water and 68.7 parts by volume of concentratedammonia is added, a stream of air is introduced, and the mixture isrefluxed with stirring until the reaction is substantially complete. Itis cooled and the product is filtered, washed with water and diluteammonia, dissolved in hot dilute ethanolic hydrochloric acid, filteredhot with charcoal and filtered again. The clarified solution is leftstanding and gradually yields orange crystals. A hotdilute ethanolicsolution of this product is clarified with charcoal made alkaline tophenolphthalein and treated with sodium hydrosulfite at the boil. Ashiny yellow product is filtered and dried at 60 C.

Example 38 To 40 parts by volume of concentrated sulfuric acid is addedwith stirring, 2.8 parts (0.04 mole) of finely ground sodium nitrite,keeping the temperature below C. The resulting solution is cooled to 5C. and a solution of 4.0 parts of 4-amin'opyridine in 10' parts ofglacial acetic acid is added dropwise at temperatures below '15 C. Themixture is stirred until diazotization is complete. The diazoniumsolution is combined with a solution of 0.04 mole of 2,6-diaminopyridinein 25 parts of glacial acetic acid at temperatures below 15 C. The brownsolution is stirred until coupling is complete and then drowned on 30parts of ice, and neutralized to pH of 7.8 with dilute caustic. Theproduct is then filtered and dried and recrystallized from absolutemethanol.

The coupling product is added to a hot solution of 5.0 parts of coppersulfate, 12.5 parts of water and 25 parts of pyridine and the mixture isrefluxed until the reaction is complete. It is then steam stripped toremove the pyridine, acidified, cooled and filtered. The orange productis dissolved in hot dilute acid, filtered and dilute caustic solution isadded to precipitate the product. This is then dissolved in hotalcoholic HCl and precipitated with concentrated ammonia to insureremoval of the copper ions. A cream colored product is filtered, washedwith water, and dried at 100 C.

Example 39 An 0.005% solution of the brightener of Example 1 is preparedby dissolving 1 part of the brightener in 1000 parts of dimethyltormamide at room temperature. This is then diluted with watercontaining a small amount of dispersing agent (Triton X-100) to the0.005% concentration. This solution is used in the following dyeingprocedure:

To a mixture of 98.5 parts of water and 1.5 parts of l 10% acetic acidsolution is added 50 parts of 0.005%

Example 40 An 0.005 solution of the brightener of Example 33 is preparedby dissolving '1 part of brightener in 1000 parts of boiling water anddiluting with water to the 0.005 concentration.

To a mixture of 98.5 parts of water and 1.5 parts of 10% acetic acidsolution is added 50 parts of the 0.005 brightener solution. To theresulting acetic acid solution of the brightener is then added a 5-partpiece of Orlon tfabric (polyacrylonitrile). The temperature is raised tothe boiling point and held there for 30 minutes. The fabric is removed,rinsed in water and dried. It is much whiter and brighter in appearancethan a piece of the untreated Orlon fabric.

Example 41 To a solution of 0.025 part of the product of Example 1 isadded 0.5 part of sodium sulfate. A piece of cotton cloth weighing 5.0parts is added and the dyebath is heated to F. After 15 minutes,another0.5 part 21 of sodium sulfate is added and heating is continued foranother 15 minutes. The cloth is then removed, rinsed at 80 F, anddried. The dyed cloth is exposed to UV light in a darkroom. Afterremoving the source of the UV light it is observed that the emission ofvisible light continues for a noticeable period.

The dyed cloth is immersed in a 5% sodium hydroxide solution and steamedat one to two pounds pressure for 1 /2 hours. The cloth is then rinsedand immersed in a bleaching solution formulated with hydrogen peroxideand sodium silicate, after which it is then steamed again at one to twopounds pressure for one hour. After rinsing in dilute acetic acid andwater and then drying, the dyed cloth is again exposed to UV light.After the removal of the source of the UV light, the emission of'visible light continues for a noticeable period, showing that thephosphorescent property of the cloth is retained after the abovefinishing treatments, typical of those to which fabrics are subjected inmanufacture.

Example 42 NH 3 N \N wherein Y is selected from the group consisting ofhy drogen, alkyl, halogen, canboxy, oarb alkoxy and carboxamide, and (2)quaternary salts of (1).

References Cited by the Examiner UNITED STATES PATENTS 3,049,438 8/1962Buell et 'al. 117-335 3,058,989 10/1962 B-uell et a1 26O-296 3,222,37112/1965 Buell et a1. 260-294.8

WALTER A. MODANCE, Primary Examiner.

ALAN L. ROTMAN, Assistant Examiner.

